The role of positron emission tomography in mediastinal mass

Mediastinal masses are a common finding in patients and can represent a diagnostic challenge for thoracic surgeons. The differential diagnosis for these masses is broad and ranges from benign solid or cystic lesions to aggressive cancers. They can present with vague symptoms, but these masses are often found incidentally in asymptomatic people. Patients with mediastinal masses should be evaluated by a multidisciplinary team of specialists, including thoracic surgeons. Determining the etiology of the mass is essential since this heavily determines the management and prognosis. The work up involves clinical evaluation, laboratory work and always involves imaging, but deciding which imaging modality will offer the most information about the lesions and guide management is not always clear. The most common imaging studies for mediastinal masses are computed tomography (CT) scans, magnetic resonance imaging (MRI), and positron emission tomography (PET) scans. The role of PET scans in the work up of these masses is not well-established, but these scans have been shown to be especially useful in certain circumstances and can help guide further work up and decision making. This review article evaluates how and when PET scans can be used to guide work up and management in a variety of mediastinal masses.